Wu Danhui, Hua Tao, Han Shuaipeng, Lan Xiuquan, Cheng Jianhua, Wen Weiqiu, Hu Yongyou
Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, College of Environment and Energy, South China University of Technology, Guangzhou, 510006, China.
Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, College of Environment and Energy, South China University of Technology, Guangzhou, 510006, China; South China Institute of Collaborative Innovation, Dongguan 523808, China.
Chemosphere. 2023 Jun;327:138514. doi: 10.1016/j.chemosphere.2023.138514. Epub 2023 Mar 25.
This study reported a novel application of MnFe-MOF-74 with two-dimensional (2D) morphology grown on carbon felt as a cathode for efficiently removing antibiotic sulfamethoxazole in the heterogeneous electro-Fenton system. Characterization demonstrated the successful synthesis of bimetallic MOF-74 by a simple one-step method. Electrochemical detection showed that the second metal addition and morphological change improved the electrochemical activity of the electrode and contributed to pollutant degradation. At pH 3 and 30 mA of current, the degradation efficiency of SMX reached 96% with 12.09 mg L HO and 0.21 mM ·OH detected in the system after 90 min. During the reaction, electron transfer between ≡Fe and ≡Mn promoted divalent metal ions regeneration, which ensured the continuation of the Fenton reaction. Two-dimensional structures exposed more active sites favoring ·OH production. The pathway of sulfamethoxazole degradation and the reaction mechanisms were proposed based on the intermediates identification by LC-MS and radical capture results. High degradation rates were still observed in tap and river water, revealing the potential of MnFe-MOF-74@CF for practical applications. This study provides a simple MOF-based cathode synthesis method, which enhances our understanding of constructing efficient electrocatalytic cathodes based on morphological design and multi-metal strategies.
本研究报道了一种新型应用，即在碳毡上生长具有二维（2D）形态的MnFe-MOF-74作为阴极，用于在非均相电芬顿系统中高效去除抗生素磺胺甲恶唑。表征结果表明通过简单的一步法成功合成了双金属MOF-74。电化学检测表明，第二种金属的添加和形态变化提高了电极的电化学活性并有助于污染物降解。在pH值为3且电流为30 mA的条件下，90分钟后系统中检测到12.09 mg L的H₂O₂和0.21 mM的·OH，磺胺甲恶唑的降解效率达到96%。在反应过程中，≡Fe和≡Mn之间的电子转移促进了二价金属离子的再生，从而确保了芬顿反应的持续进行。二维结构暴露了更多有利于·OH生成的活性位点。基于液相色谱-质谱联用（LC-MS）对中间体的鉴定和自由基捕获结果，提出了磺胺甲恶唑的降解途径和反应机理。在自来水和河水中仍观察到较高的降解率，揭示了MnFe-MOF-74@CF在实际应用中的潜力。本研究提供了一种基于MOF的简单阴极合成方法，增进了我们对基于形态设计和多金属策略构建高效电催化阴极的理解。
